Known Limitations

This page describes known limitations of the Illumina TruPath Genome software solution.

Functionality

• This software solution will only work with the Illumina TruPath Genome prep on the Nova Seq X Instrument Series

  • NovaSeq X Instrument must be upgraded to 1.4 SW.

  • Indexing is currently not supported with the Illumina TruPath Genome prep. One sample per flow cell lane is currently supported.

  • Using non-TruPath data inputs to DRAGEN will lead to analysis failure.

Performance

• Due to FPGA memory limitations, on-prem analysis for the Illumina TruPath Genome requires a phase 4 DRAGEN server. For reference, phase 4 servers have a server serial number which begins with the letters "AC".

• MRJD requires at least 16x coverage to make calls; the caller will abort any attempt to call genes with insufficient aligned read coverage.

Variant Calling

• Any additional variant callers are not supported, and any data generated by them has not been validated

• Variant calling is only currently supported for human reference genomes

  • If required, non-human reference genomes must be uploaded in a v12 file format. These will not produce variant calls that the Illumina team supports.

Downsampling

• Fractional downsampling is not supported in TruPath. This downsampling method disrupts proximity information, leading to degraded secondary analysis performance.